1. Field of the Invention
The present invention relates to a method for recognizing the polarity of polarized capacitors, particularly tantalum and aluminum electrolytic capacitors in automatic equipping of printed circuitboards and ceramic substrates, and is also concerned with an apparatus for implementation of the method.
2. Description of the Prior Art
In automatic equipping of printed circuitboards and ceramic substrates with electronic components such as resistors, capacitors, diodes, transistors, chips and the like, the various components are offered in laterallyarranged feeder devices. The removal of the components then occurs via an equipping head which grasps the respective component offered in a removal position, centers the component with the assistance of four forceps-like levers arranged in pairs, and deposits the component on a predetermined location on the printed circuitboard or of the ceramic substrate. The reliability of equipping obtainable with such automatic equipping units known, for example, from U.S. Pat. No. 4,155,630, fully incorporated herein by this reference, critically depends on the equipping head programmed for the removal position of the feeder devices always encountering the components in the proper position and likewise depositing the component in the proper position in the program equipping position of the printed circuitboard or of the ceramic substrate.
In an equipping head disclosed in the German No. A 3 102 206, at least the lower end of the suction pipette serving the purpose of picking up the components is composed of an electrically non-conductive material, whereby the forceps-shaped ends of the lever interacting with the electronic component are arranged in an electrically insulated manner. As a result of this measure, a defined current can be supplied via a pair of levers or a defined voltage can be applied via a pair of levers. In particular, there is the possibility of measuring or testing the electrical characteristics of the component respectively seized by the equipping head. However, a recognition of the polarity of polarized capacitors that is absolutely necessary for automatic equipping is not possible with the mentioned equipping head since suitable electrical recognition methods have been heretofore unknown.